4 (0x04) read input resgisters, 5 (0x05) write single coil, Specification – Beijer Electronics NA-9379 User Manual
Page 12

NA-9379
Specification
Revision 1.02
FnBus PIO N/A
Page 12
3.1.4.
4 (0x04) Read Input Resgisters
This function code is used to read from 1 to approx. 125 contiguous input registers in a remote device. The Request
PDU specifies the starting register address and the number of registers. The register data in the response message are
packed as two bytes per register, with the binary contents right justified within each byte. For each register, the first byte
contains the high order bits and the second contains the low order bits.
•
Request
Field name
Example
Function Code
0x04
Starting Address Hi
0x00
Starting Address Lo
0x00
Quantity of Register Hi
0x00
Quantity of Register Lo
0x02
•
Response
Field name
Example
Function Code
0x03
Byte Count
0x04
Input Register#0 Hi
0x00
Input Register#0 Lo
0x80
Input Register#1 Hi
0x00
Input Register#1 Lo
0x00
- In case of address 0x0000, 0x0001 input register value: 0x0080, 0x0000.
3.1.5.
5 (0x05) Write Single Coil
This function code is used to write a single output to either ON or OFF in a remote device. The requested ON/OFF state
is specified by a constant in the request data field. A value of FF 00 hex requests the output to be ON. A value of 00 00
requests it to be OFF. All other values are illegal and will not affect the output.
•
Request
Field name
Example
Function Code
0x05
Output Address Hi
0x10
Output Address Lo
0x01
Output Value Hi
0xFF
Output Value Lo
0x00
•
Response
Field name
Example
Function Code
0x05
Output Address Hi
0x10
Output Address Lo
0x01
Output Value Hi
0xFF
Output Value Lo
0x00
- Output bit of address 0x1001 turns ON.
PRELIMINARY